Gene Summary

Gene:

GPC3; glypican 3

Aliases:

SGB, DGSX, MXR7, SDYS, SGBS, OCI-5, SGBS1, GTR2-2

Location:

Xq26.1

Summary:

Cell surface heparan sulfate proteoglycans are composed of a membrane-associated protein core substituted with a variable number of heparan sulfate chains. Members of the glypican-related integral membrane proteoglycan family (GRIPS) contain a core protein anchored to the cytoplasmic membrane via a glycosyl phosphatidylinositol linkage. These proteins may play a role in the control of cell division and growth regulation. The protein encoded by this gene can bind to and inhibit the dipeptidyl peptidase activity of CD26, and it can induce apoptosis in certain cell types. Deletion mutations in this gene are associated with Simpson-Golabi-Behmel syndrome, also known as Simpson dysmorphia syndrome. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Sep 2009]

Latest Publications: GPC3 (cancer-related)

UNLABELLED: Hepatocellular carcinoma (HCC) is an increasingly lethal malignancy for which management is critically dependent on accurate imaging. Glypican-3 (GPC3) is a cell surface receptor overexpressed in most HCCs and provides a unique target for molecular diagnostics. The use of monoclonal antibodies (mAbs) that target GPC3 (αGPC3) in PET imaging has shown promise but comes with inherent limitations associated with mAbs such as long circulation times. This study used (89)Zr-conjugated F(ab')2 fragments directed against GPC3 ((89)Zr-αGPC3-F(ab')2) to evaluate the feasibility of the fragments as a diagnostic immuno-PET imaging probe.METHODS: Immobilized ficin was used to digest αGPC3, creating αGPC3-F(ab')2 fragments subsequently conjugated to (89)Zr. In vivo biodistribution and PET studies were performed on GPC3-expressing HepG2 and GPC3-nonexpressing RH7777 orthotopic xenografts.RESULTS: Reliable αGPC3-F(ab')2 production via immobilized ficin digestion was verified by high-performance liquid chromatography and sodium dodecyl sulfate polyacrylamide gel electrophoresis. (89)Zr-αGPC3-F(ab')2 demonstrated F(ab')2-dependent, antigen-specific cell binding. HepG2 tumor uptake was higher than any other tissue, peaking at 100 ± 21 percentage injected dose per gram (%ID/g) 24 h after injection, a value 33- to 38-fold higher than GPC3-nonexpressing RH7777 tumors. The blood half-life of the (89)Zr-αGPC3-F(ab')2 conjugate was approximately 11 h, compared with approximately 115 h for historic mAb controls. This shorter half-life enabled clear tumor visualization on PET 4 h after administration, with a resultant peak tumor-to-liver contrast ratio of 23.3. Blocking antigen-expressing tumors with an excess of nonradiolabeled αGPC3 resulted in decreased tumor uptake similar to native liver. The kidneys exhibited high tissue uptake, peaking at 24 h with 83 ± 12 %ID/g. HepG2 tumors ranging from 1.5 to 7 mm were clearly visible on PET, whereas larger RH7777 tumors displayed signal lower than background liver tissue.CONCLUSION: This study demonstrates the feasibility of using (89)Zr-αGPC3-F(ab')2 for intrahepatic tumor localization with small-animal PET. Faster blood clearance and lower background liver uptake enable excellent signal-to-noise ratios at early time points. Increased renal uptake is similar to that as has been seen with clinical radioactive peptide imaging. (89)Zr-αGPC3-F(ab')2 addresses some of the shortcomings of whole-antibody immuno-PET probes. Further optimization is warranted to maximize probe sensitivity and specificity in the process of clinical translation.

UNLABELLED: Genetic determinants of the early steps of carcinogenesis on cirrhosis are still poorly understood. We aimed to evaluate the occurrence of telomerase reverse transcriptase (TERT) promoter mutations in the transformation of cirrhotic nodules into hepatocellular carcinoma (HCC). We analyzed a series of 268 liver samples, including 96 nodules developed in 58 patients with cirrhosis and 114 additional cirrhosis. All samples were screened for TERT promoter mutations, and in 31 nodules, for 10 genes recurrently mutated in HCC. Immunohistochemistry (IHC) analyses were performed for glypican 3, glutamine synthase, and heat shock protein 70. Six liver pathologists reviewed all the samples. Among The 96 nodules, 88 were firmly diagnosed as low-grade dysplastic nodules (LGDNs; 32 cases), high-grade dysplastic nodules (HGDNs; 16 cases), early HCC (eHCC; 23 cases), or small and progressed HCC in 17 cases. The agreement between the initial diagnosis from pathological report and the final expert consensus report was moderate for the diagnosis of benign versus malignant nodules (weighted kappa = 0.530). TERT promoter mutations were highly related to the step-wise hepatocarcinogenesis because mutations were identified in 6% of LGDNs, 19% of HGDNs, 61% of eHCCs, and 42% of small and progressed HCC. TERT promoter mutation is the most frequent molecular alteration in eHCC given that the IHC criteria for diagnosis of malignancy were found in only 39% of the cases. TERT promoter mutation was also the earliest genetic alteration because mutations in 10 other genes were only identified in 28% of the small and progressed HCC.CONCLUSION: Frequency of TERT promoter mutations rapidly increases during the different steps of the transformation of premalignant lesions into HCC on cirrhosis. Consequently, somatic TERT promoter mutation is a new biomarker predictive of transformation of premalignant lesions into HCC.

AIMS: In contrast to clear cell carcinomas developing in other organs (e.g. ovary and uterus), gastric adenocarcinomas with clear cell features are not well characterized.METHODS AND RESULTS: We evaluated a series of 762 gastric adenocarcinomas for the presence of clear cell changes; and investigated the nature of the changes using several histochemical and immunohistochemical markers, their association with various clinicopathological features, and their prognostic significance. Clear cell changes were observed in 8.5% (n = 65) of gastric cancers. Cases with clear cell changes (GCC) were associated significantly with older age, intestinal type histology, body/fundic location, greater depth of invasion, lymph node metastases and lymphovascular invasion. An increasing proportion of clear cell changes indicated a worsening prognosis, and was identified as an independent marker of poor prognosis using the Cox proportional hazard model (hazard ratio, 0.462; P = 0.003). Of 62 GCCs subjected to special staining, 35 cases (55.6%) displayed cytoplasmic accumulation of glycogen, while 21 (33.3%) contained mucin. GCCs showing glycogen accumulation expressed AFP, glypican-3 and CD10 more commonly than those with mucin, which commonly expressed Muc5AC and Muc6.CONCLUSION: Clear cell gastric adenocarcinoma is a unique subgroup of gastric cancer which, although heterogeneous, has a poor prognosis.

There is a significant sex disparity favoring males among hepatocellular carcinoma (HCC) patients. Although various risk factors have been identified, the exact etiology of such sexual dimorphism(s) in HCC is uncertain. Previous studies showed that overexpression of the Y-located protooncogene, testis-specific protein Y encoded (TSPY), promotes cell proliferation and oncogenesis whereas its X-located homologue, TSPYhomologue X (TSPX), retards cell cycle and oncogenic progression. Furthermore, TSPX promotes proteasomal degradation of hepatitis B virus-encoded X oncoprotein and hence could serve as a tumor suppressor in virus-associated HCC. Using immunohistochemistry and reverse-transcription polymerase chain reaction analysis, we had examined the expression of TSPY and TSPX with reference to other established biomarkers in HCC and related liver cancers. Our results demonstrated that 55 (19.2%) of 287 male cases were TSPY positive in immunohistochemistry of tissue arrays, and 15 (46.9%) of 32 male cases were TSPY positive in reverse-transcription polymerase chain reaction analysis of clinical samples. TSPY expression was closely associated with the expression of HCC biomarkers, such as glypican 3. In contrast, TSPX expression was down-regulated in 54.5% of total tumor/nontumorous paired samples (18/33) and negatively associated with those of TSPY, glypican 3, and forkhead box M1 (FOXM1) and was positively associated with that of a tumor suppressor, insulin-like growth factor binding protein 3. The present findings support the hypothesis that the oncogenic events leading to an ectopic activation of the Y-located protooncogene TSPY and/or inactivating mutation/epigenetic silencing of the X-located tumor suppressor gene TSPX could collectively contribute to the sexual dimorphism(s) in HCC and related liver cancers in male-biased manners.

Neuroblastoma prognosis is dependent on both the differentiation state and stromal content of the tumor. Neuroblastoma tumor stroma is thought to suppress neuroblast growth via release of soluble differentiating factors. Here, we identified critical growth-limiting components of the differentiating stroma secretome and designed a potential therapeutic strategy based on their central mechanism of action. We demonstrated that expression of heparan sulfate proteoglycans (HSPGs), including TβRIII, GPC1, GPC3, SDC3, and SDC4, is low in neuroblasts and high in the Schwannian stroma. Evaluation of neuroblastoma patient microarray data revealed an association between TGFBR3, GPC1, and SDC3 expression and improved prognosis. Treatment of neuroblastoma cell lines with soluble HSPGs promoted neuroblast differentiation via FGFR1 and ERK phosphorylation, leading to upregulation of the transcription factor inhibitor of DNA binding 1 (ID1). HSPGs also enhanced FGF2-dependent differentiation, and the anticoagulant heparin had a similar effect, leading to decreased neuroblast proliferation. Dissection of individual sulfation sites identified 2-O, 3-O-desulfated heparin (ODSH) as a differentiating agent, and treatment of orthotopic xenograft models with ODSH suppressed tumor growth and metastasis without anticoagulation. These studies support heparan sulfate signaling intermediates as prognostic and therapeutic neuroblastoma biomarkers and demonstrate that tumor stroma biology can inform the design of targeted molecular therapeutics.

PURPOSE: Our aims are to determine levels of circulating cellular and protein biomarkers in hepatocellular carcinoma (HCC) patients and to analyse any relationships with clinical parameters.METHODS: Fifty-four consenting patients were recruited. Circulating tumour cells (CTCs) were enumerated (by CellSearch) and characterised via filtration [by isolation by size of epithelial tumour cells (ISET)] with downstream immunohistochemistry (IHC). Glypican-3 (GPC3) expression in tumour biopsies and CTCs (by IHC) was compared, and levels of circulating caspase-cleaved and full-length cytokeratin 18 (CK18, measured using M30 and M65 ELISAs) were examined as a putative prognostic factor and marker of tumour burden.RESULTS: CTCs were identified in 14 out of 50 (28%) patients by CellSearch and in 19 out of 19 (100%) patients by ISET. The presence of GPC3-positive CTCs by ISET was 100% concordant with the presence of GPC3-positive cells in the original tumour (n = 5). No statistically significant correlations were observed between CTC number and clinical characteristics, although trends were noted between CTC subtypes, Child-Pugh score and tumour node metastasis stage. Serum M30 and M65 levels (as continuous variables) significantly correlated with overall survival (OS) in a univariate analysis (p = 0.003 and p < 0.001, respectively); M65 levels remained statistically significant in a multivariate analysis (p = 0.029).CONCLUSIONS: This is the first study to detect GPC3-positive CTCs in HCC, important for drug development with this target. The significant association of circulating CK18 with OS in HCC further exemplifies the utility of circulating biomarkers in cancer.

Somatic-type malignancies (SMs) in patients with testicular germ cell tumors (GCT) are rare and mostly attributed to "transformation" of teratoma, although yolk sac tumor (YST) origin has also been proposed. We studied 124 cases of "SM" of testicular GCT origin from 106 patients to evaluate their morphology, immunohistochemical features (especially the utility of SALL4), and relationship to YST. Primitive neuroectodermal and nephroblastomatous tumors were excluded because of prior studies. Patients ranged in age from 15 to 68 years (mean, 33 y). The tumors ranged from 0.7 to 30 cm (mean, 7.6 cm) and involved the retroperitoneum (64%), abdomen/pelvis (10%), lung (10%), mediastinum (6%), supraclavicular region/neck (4%), testis (4%), and thigh (1%). Most initial diagnoses were sarcomas (n=68) or carcinomas (n=51). On review and immunohistochemical analysis, 7 of 45 adenocarcinomas were reclassified as glandular YSTs (GYST) on the basis of glypican-3 (GPC3) and/or α-fetoprotein positivity and scant/absent reactivity for EMA and CK7. These occasionally (29%) had subnuclear and sometimes supranuclear vacuoles (endometrioid-like), whereas adenocarcinomas were more frequently mucinous (17%) or enteric-type (11%) than endometrioid-like (9%). Both expressed CDX2 frequently (83% and 63%, respectively). MUC protein 2, 4, 5, and 6 expression was more common in adenocarcinomas (7% to 36%) than in GYSTs (0% to 20%) but was infrequent. Both were often positive for SALL4, BerEP4, and MOC31; all were negative for TTF-1. On follow-up (GYST: range, 23 to 169 mo; mean, 81mo; adenocarcinoma: range, 1 to 170 mo; mean, 55 mo), 50% and 33% of patients with GYST and adenocarcinoma, respectively, died of disease. We reclassified 26 of 76 sarcomatoid tumors as sarcomatoid YSTs (SYST) on the basis of positive reactivity for both AE1/3 and GPC3. These tumors often had spindled and epithelioid cells in a fibromyxoid stroma. SYSTs were often (60%) SALL4 positive, whereas sarcomas were all negative. On follow-up (SYST: range, 1 to 259 mo; mean, 62 mo; sarcoma: range, 1 to 327 mo; mean, 70 mo), 50% and 29% of patients with SYST and sarcoma, respectively, died of disease, with most mortality occurring in those with high-grade tumors. We conclude that, on the basis of a panel of immunoreactivities, a significant number of "SMs" in testicular GCT patients are more accurately classified as either GYSTs or SYSTs. Ambiguous glandular tumors should be evaluated for GPC3, α-fetoprotein, CK7, and EMA reactivity and sarcomatoid ones for GPC3, AE1/3, and SALL4 reactivity.

OBJECTIVE: To study the expression of arginase-1 (Arg-1), glypican-3 (GPC3), hepatocyte paraffin antigen 1 (HepPar-1) and alpha-fetoprotein (AFP) in hepatocellular carcinoma (HCC), benign liver lesions (BLL) and metastatic carcinoma (MC), and their applications in diagnosis and differential diagnosis.METHODS: Immunohistochemical study (EnVision method) for Arg-1, GPC3, HepPar-1 and AFP was carried out in three groups of liver lesions, including 85 cases of HCC, 35 cases of BLL and 19 cases of MC. The relationship between expression of Arg-1, GPC3, HepPar-1 and AFP and clinicopathologic features in HCC was also analyzed.RESULTS: The positive expression rate of Arg-1 was 90.6% (79/85) in HCC and 100% (35/35) in BLL. Arg-1 expression was observed in 1 of the 19 cases of MC studied. The positive expression rate of GPC3 was 82.4% (70/85) in HCC, 5.3% (1/19) in MC and 0 (0/35) in BLL. The positive expression rate of AFP was 47.1% (40/85) in HCC and 0 in BLL or MC. The positive expression rate of HepPar-1 was 72.9% (62/85) in HCC, 100% (35/35) in BLL and 2/19 in MC. Arg-1 has a higher sensitivity in highlighting hepatocellular lesions than AFP and HepPar-1 (P=0.000 versus P=0.002). The specificity of GPC3 expression in HCC was 98.1%.CONCLUSIONS: Arg-1 is a sensitive hepatocellular marker in delineation of liver lesions.GPC3 is a relatively specific marker in diagnosis of HCC.

Dr Robert E. Scully greatly advanced our understanding of germ cell neoplasia to the extent that it is difficult to narrow the discussion of his contributions to this topic so that it can be covered in a brief article. This article accordingly focuses on some of the recent developments concerning 2 of his major contributions in this area-the gonadoblastoma (GB) and variant morphologies of yolk sac tumor. GB was defined by Dr Scully in 1953 and its features elaborated in detail by him in 1970. This neoplasm occurred in young patients who often displayed phenotypic sex ambiguities and frequently presented with primary amenorrhea. It was bilateral in 40%, and consisted of circumscribed nests of small sex cord cells and germinoma-like cells admixed with round deposits of eosinophilic, hyaline, often calcified material. These nests were set in a spindle cell gonadal stroma with Leydig-like or lutein-like cells. Because of his work we now understand that this precursor to invasive germ cell tumors occurs in patients with a specific form of disorder of sex development, namely gonadal dysgenesis, and only in those who have a particular portion of the Y chromosome, the GB locus/TSPY gene, within the gonadal tissue. An essential element to the development of GB appears to be a defect in the genetic pathway that leads to the development of Sertoli cells. Improperly formed Sertoli cells predispose to "delayed maturation" of the gonocytes of the gonad and predispose them to undergo malignant transformation. "Undifferentiated gonadal tissue" has been proposed as the precursor to the development of GB and consists of an unorganized mixture of apparently non-neoplastic germ cells, germ cells with delayed maturation, and neoplastic germ cells with sex cord cells and gonadal stroma. Two variant morphologies of yolk sac tumor were also recognized by Dr Scully. In the hepatoid variant features similar to hepatocellular carcinoma occurred, although primitive glandular foci and lack of liver involvement permitted its distinction in most cases. More recently this variant has been found to occasionally produce bile in canalicular-like structures and to stain strongly for both SALL4 and glypican 3, 2 recently described markers of yolk sac tumor. Recognition of hepatoid yolk sac tumor was followed by the description of a potential mimic, primary ovarian hepatoid carcinoma, which, however, occurred in a significantly older patient population and was occasionally associated with surface epithelial neoplasia. The endometrioid-like variant of yolk sac tumor simulated primary endometrioid adenocarcinoma. It can be suspected on routine stains because of primitive appearing nuclei, frequent subnuclear vacuoles, and in some cases association with more usual yolk sac tumor. Its recognition is now facilitated by a panel of immunohistochemical stains that are often expressed differentially in these 2 neoplasms--endometrioid-like yolk sac tumor: positive for SALL4, glypican 3, and α-fetoprotein; endometrioid adenocarcinoma: positive for cytokeratin 7 and epithelial membrane antigen. Finally, Dr Scully contributed one of the first cases in the literature of yet another nuance in the complicated world of yolk sac neoplasia, namely the development of some tumors on the background of a surface epithelial neoplasm. This is analogous to the more common development of choriocarcinoma from carcinoma and, in the case of yolk sac tumor, diagnosis is aided clinically by the usual older age of the patient and nature of the associated neoplasia.

BACKGROUND/AIMS: DNA-based tumor vaccine immunotherapy which elicits exclusively cellular immune response against cancer cells in an antigen-specific fashion has been documented to be an effective treatment for cancers in the past decade. Glypican 3 (GPC3) is especially overexpressed in hepatocellular carcinoma (HCC), but not in benign liver lesions and normal adult tissues, which makes it an ideal tumor antigen designed for HCC immunotherapy.METHODOLOGY: We constructed a GPC3 cDNA vaccine by using a recombinant plasmid encoding murine GPC3 cDNA for treatment of HCC in a C57BL/6 mouse model. The specificity and effectiveness of anti-tumor immunity were assessed in vitro and in vivo studies.RESULTS: In vitro studies showed that GPC3 DNA vaccine induced potent specific cytotoxic T lymphoctyes (CTLs) immune response against C57BL/6 homogenous HCC cell line Hepa 1-6 (GPC3+). However, there was no detectable immune response against GPC3-negative SP 2/0 cells and Sk-Hep-1 cells. In vivo study indicated that GPC3 DNA vaccine could significantly suppress homogenous tumor growth and prolong survival time of tumor bearing mice.CONCLUSIONS: This study demonstrated the first time that the GPC3 DNA vaccine could elicit specific and effective cellular antitumor immunity against GPC3 HCC. This may provide an alternative option for immunotherapy of HCC.

Cancer immunotherapy is a promising new approach to cancer treatment. It has been demonstrated that a high number of tumor-specific cytotoxic T cells (CTLs) is associated with increased disease-specific survival in lung cancer patients. Identification of superior CTL epitopes from tumor antigens is essential for the development of immunotherapy for malignant tumors. The EML4-ALK fusion gene was recently identified in a subset of non-small cell lung cancers (NSCLCs). In this study we searched for HLA-A 02:01- and HLA-A 24:02‑restricted epitopes derived from EML4-ALK by screening predicted EML4-ALK‑derived candidate peptides for the induction of tumor‑reactive CTLs. Nine EML4-ALK‑derived peptides were selected by a computer algorithm based on a permissive HLA-A 02:01 or HLA-A 24:02 binding motif. One of the nine peptides induced peptide-specific CTLs from human peripheral blood mononuclear cells. We were able to generate a peptide‑specific CTL clone. This CTL clone specifically recognized peptide‑pulsed T2 cells and H2228 cells expressing HLA-A 02:01 and EML4-ALK that had been treated with IFN-γ 48 h prior to examination. CTL activity was inhibited by an anti-HLA‑class I monoclonal antibody (W6/32), consistent with a class I-restricted mechanism of cytotoxicity. These results suggest that this peptide (RLSALESRV) is a novel HLA-A 02:01-restricted CTL epitope and that it may be a new target for antigen-specific immunotherapy against EML4‑ALK-positive cancers.

BACKGROUND: Hepatocellular carcinoma (HCC) is usually asymptomatic in the early stage and does not show elevated alpha-feto protein (AFP). AFP shows 60-80% sensitivity in diagnosing HCC. Glypican3 (GPC-3) is an oncofetal protein that is only detected in HCC cells but not in benign liver tissues, while Carcinoembryonic antigen (CEA) is expressed in various neoplasms including HCC. Although, it is not specific for HCC. Prothrombin induced by vitamin K absence-II (PIVKA-II) is an abnormal prothrombin protein that is increased in the serum of HCC patients. It has higher sensitivity and specificity compared to AFP. The aim of this study is to compare the clinical utility of PIVKA-II with GPC-3, AFP and CEA in diagnosing HCC.PATIENTS AND METHODS: This study included 40 patients with HCC, 10 patients with cirrhosis as a benign control group, and 10 apparently healthy volunteers as normal controls. Serum samples were subjected to routine laboratory investigations, measurement of CEA, AFP using MEIA technique (Axsym), glypican3, and PIVKA-II using ELISA technique in the sera of all patients and controls.RESULTS: All markers showed the highest results in the HCC group. Higher concentrations of PIVKA-II were detected in patients with splenomegaly, and in tumors with size (>3cm). Combination of Glypican-3 and PIVKA-II showed the highest sensitivity, while GPC-3 alone and combination of GPC-3 and AFP showed the highest specificity to differentiate HCC from liver cirrhosis and normal controls. GPC-3, PIVKAII, and combination of both showed the highest sensitivity, while GPC-3 alone showed the highest specificity to differentiate HCC from liver cirrhosis.CONCLUSION: Glypican-3 is the only oncofetal antigen that showed comparable high diagnostic accuracy as PIVKA-II in diagnosing HCC among Egyptian patients.

Imaging probes for early detection of hepatocellular carcinoma (HCC) are highly desired to overcome current diagnostic limitations which lead to poor prognosis. The membrane protein glypican-3 (GPC3) is a potential molecular target for early HCC detection as it is over-expressed in >50% of HCCs, and is associated with early hepatocarcinogenesis. We synthesized the positron emission tomography (PET) probe (89)Zr-DFO-1G12 by bioconjugating and radiolabeling the anti-GPC3 monoclonal antibody (clone 1G12) with (89)Zr, and evaluated its tumor-targeting capacity. In vitro, (89)Zr-DFO-1G12 was specifically taken up into GPC3-positive HCC cells only, but not in the GPC3-negative prostate cancer cell line (PC3). In vivo, (89)Zr-DFO-1G12 specifically accumulated in subcutaneous GPC3-positive HCC xenografts only, but not in PC3 xenografts. Importantly, (89)Zr-DFO-1G12 delineated orthotopic HCC xenografts from surrounding normal liver, with tumor/liver (T/L) ratios of 6.65 ± 1.33 for HepG2, and 4.29 ± 0.52 for Hep3B xenografts. It also delineated orthotopic xenografts derived from three GPC3-positive HCC patient specimens, with T/L ratios of 4.21 ± 0.64, 2.78 ± 0.26, and 2.31 ± 0.38 at 168 h p.i. Thus, (89)Zr-DFO-1G12 is a highly translatable probe for the specific and high contrast imaging of GPC3-positive HCCs, which may aid early detection of HCC to allow timely intervention.

Ovarian cancer is the leading cause of death among gynaecological malignancies. Extracellular matrix (ECM) can affect drug resistance by preventing the penetration of the drug into cancer cells and increased resistance to apoptosis. This study demonstrates alterations in the expression levels of ECM components and related genes in cisplatin-, doxorubicin-, topotecan-, and paclitaxel-resistant variants of the A2780 ovarian cancer cell line. Affymetrix Gene Chip Human Genome Array Strips were used for hybridisations. The genes that had altered expression levels in drug-resistant sublines were selected and filtered by scatter plots. The genes that were up- or downregulated more than fivefold were selected and listed. Among the investigated genes, 28 genes were upregulated, 10 genes were downregulated, and two genes were down- or upregulated depending on the cell line. Between upregulated genes 12 were upregulated very significantly--over 20-fold. These genes included COL1A2, COL12A1, COL21A1, LOX, TGFBI, LAMB1, EFEMP1, GPC3, SDC2, MGP, MMP3, and TIMP3. Four genes were very significantly downregulated: COL11A1, LAMA2, GPC6, and LUM. The expression profiles of investigated genes provide a preliminary insight into the relationship between drug resistance and the expression of ECM components. Identifying correlations between investigated genes and drug resistance will require further analysis.

Hepatoid or α-fetoprotein (AFP)-producing adenocarcinomas of stomach growing in a solid pattern are highly aggressive tumors. It is difficult to detect hepatoid differentiation solely based on findings from hematoxylin and eosin stainings, especially in small biopsy specimens. Gastric adenocarcinomas with hepatoid differentiation should be distinguished from solid-type gastric adenocarcinoma because of their different biological behavior. We immunohistochemically analyzed hepatocellular markers (AFP, glypican 3, and Hepatocyte paraffin 1 [HepPar-1]) and possible markers of gastric hepatoid adenocarcinoma (Sal-like protein 4 [SALL4] and palate, lung, and nasal epithelium carcinoma-associated protein [PLUNC]) to detect hepatoid differentiation in 45 gastric hepatoid adenocarcinomas and 47 nonhepatoid solid-type poorly differentiated adenocarcinomas. There were a higher incidence of vascular invasion (P = .0055) and distant metastasis (P = .0458) in hepatoid adenocarcinoma than in nonhepatoid adenocarcinoma. AFP, SALL4, HepPar-1, and glypican 3 were significantly higher in hepatoid adenocarcinoma than in nonhepatoid adenocarcinoma. All 5 markers were positive in both the hepatoid/solid and the tubular component. In hepatoid adenocarcinoma, the frequency of distant metastasis was significantly higher in SALL4-negative cases than in SALL4-positive cases (P = .0381). HepPar-1 was associated with liver metastasis (P = .0452). PLUNC was correlated with lymph node metastasis (P = .0375). There was a significant difference in the survival rate between HepPar-1-positive and HepPar-1-negative groups (P = .0437). The coexpression of PLUNC and SALL4 and the other coexpression of HepPar-1 and PLUNC were associated with poorer prognosis (P = .0181 and P = .0443, respectively). AFP, SALL4, HepPar-1, and glypican 3 are useful for the detection of hepatoid differentiation. A combination of PLUNC, HepPar-1, and SALL4 could be a reliable prognostic indicator in hepatoid adenocarcinoma of the stomach.

Aldo-keto reductase family 1, member B10 (AKR1B10), a cancer-related oxidoreductase, is expressed in well-differentiated hepatocellular carcinomas (HCCs). However, AKR1B10 levels are minimal in normal liver tissues (NLs), similar to the 70-kilodalton heat shock protein (HSP70) and glypican-3. Moreover, the role of AKR1B10 in chronic hepatitis or cirrhosis, which are considered preneoplastic conditions for HCC, has not been fully elucidated. The aim of this study was to evaluate the expression of AKR1B10, HSP70, and glypican-3 in 61 HCC tissue samples compared to corresponding non-tumorous liver tissues (NTs), comprising 42 chronic hepatitis and 19 cirrhosis cases to clarify the significance of molecular changes at the preneoplastic stages of HCC. Immunohistochemical analysis demonstrated that the median expression levels of AKR1B10 were higher in HCCs than in NTs (p<0.001) and higher in NTs than NLs (p<0.001) with 54.8%, 2.1%, and 0.3% expression in HCCs, NTs, and NLs, respectively. HSP70 and glypican-3 were expressed in HCCs, but minimally in NTs and NLs with no significant difference between expression in NTs and NLs. Furthermore, a multivariate analysis identified an association between hepatic steatosis and AKR1B10 expression in NTs (p=0.020). Of the three protein expressed in well-differentiated HCCs, only AKR1B10 was upregulated in preneoplastic conditions, and a steatosis-related factor might influence its expression.

Intrahepatic cholangiocarcinoma (ICC) is the second most common primary liver cancer next to hepatocellular carcinoma (HCC). Despite the significant difference of the therapeutic strategy for both diseases, their histological appearance may be very similar. Thus the correct diagnosis is crucial for treatment choice but is often difficult to achieve. The aim of our study was to evaluate anterior gradient 3 (AGR3) as a new diagnostic marker helping to distinguish between ICC and HCC. AGR3 is a putative transmembrane protein implicated in breast, prostate and ovary tumorigenesis and belongs to the family of protein disulfide isomerases. Since there is little information on how AGR3 is expressed in normal and diseased tissues and what its exact function is, we analyzed its expression pattern in normal liver and tumor tissue of ICC and HCC. The immunohistochemical analysis in normal tissue revealed specific AGR3 expression in intrahepatic bile duct cholangiocytes which was not present in liver hepatocytes. Consequently we analyzed AGR3 expression in 74 representative samples of puncture biopsies, tissue excisions and resection specimens from which 48 samples were diagnosed as HCC and 26 as ICC. Our results showed AGR3 expression negative and weakly positive respectively in hepatocellular carcinomas compared to stronger AGR3 positivity in cholangiocellular carcinomas. AGR3 expression statistically significantly correlated to acid mucopolysaccharide expression and negatively correlated to glypican-3 expression. We conclude that according to receiver operating characteristics (ROC) analysis AGR3 expression is relatively specific for ICC and is potentially linked to mucosecretion, which may indicate potential implication in treatment resistance.

BACKGROUND/AIMS: α-Fetoprotein (AFP) is the biomarker most widely used to detect hepatocellular carcinoma (HCC), despite its suboptimal diagnostic accuracy. Glypican-3 (GPC3) and osteopontin (OPN) are secreted glycoproteins that are reportedly associated with tumorigenesis and metastasis. This study was conducted to evaluate the clinical utility of using plasma GPC3 and OPN as diagnostic biomarkers for HCC.METHODS: We measured the plasma levels of GPC3 and OPN in 120 HCC and 40 chronic liver disease (CLD) patients via an enzyme-linked immunosorbent assay. The diagnostic accuracy of each tumor marker was evaluated using receiver operating characteristic (ROC) curve analysis.RESULTS: The GPC3 levels in the HCC patients (75.8 ng/mL) were significantly higher (p=0.020) than the levels in patients with CLD (66.4 ng/mL). The area under the ROC curve (AUROC) values for GPC3 and OPN were 0.62 and 0.51, respectively. In subgroup analyses, including subgroups of HCC patients with low serum AFP and PIVKA II levels, the AUROC of GPC3 remained relatively high (0.66), and GPC3 showed a high sensitivity (62.1%) for detecting small HCC tumors.CONCLUSIONS: The plasma levels of GPC3 and OPN demonstrated low diagnostic accuracy for HCC. However, GPC3 may have a complementary role in diagnosing HCC in patients with nondiagnostic levels of conventional tumor markers and with small-sized tumors.

Glypican-3 (GPC-3), a membrane-associated heparan sulfate proteoglycan, plays a crucial role in cell proliferation and metastasis, particularly in hepatocellular carcinoma (HCC) progression, and perhaps is a valuable target for its gene therapy. However, its mechanism remains to be explored. In the present study, the biological behaviors of HCC cells were investigated by interfering GPC-3 gene transcription. After the cells were transfected with specific GPC-3 short hairpin RNA (shRNA), the inhibition of GPC-3 expression was 75.6 % in MHCC-97H or 73.8 % in Huh7 cells at mRNA level; the rates of proliferation and apoptosis were 53.6 and 60.5 % in MHCC-97H or 54.9 and 54.4 % in Huh7 cells, with the cell cycles arrested in the G1 phase; the incidences of cell migration, metastasis, and invasion inhibition were 80.1, 56.4, and 69.1 % in MHCC-97H or 80.9, 59.6, and 58.3 % in Huh7 cells, respectively. The cell biological behaviors were altered by silencing GPC-3 with down-regulation of β-catenin, insulin-like growth factor-II and vascular endothelial growth factor, and Gli1 up-regulation. The cell proliferation was significantly inhibited (up to 95.11 %) by shRNA plus anti-cancer drugs, suggesting that GPC-3 gene should be a potential target for promoting hepatoma cell apoptosis and inhibiting metastasis through the Wnt/β-catenin and Hh singling pathways.

BACKGROUNDS: Glypican-3(GPC3) has been implicated in tumor development and progression for several years. However, the prognostic significance of GPC3 expression in patients with hepatocellular carcinoma (HCC) is controversial. We performed a meta-analysis of available studies to assess whether GPC3 can be used as a prognostic factor in patients with HCC.METHODS: We searched PubMed and Ovid EBM Reviews databases and evaluated the reference list of relevant articles for studies that assessed the prognostic relevance of GPC3 in patients with HCC. Meta-analysis was performed using hazard ratio (HR) or odds ratio (OR) and 95% confidence intervals (95% CIs) as effect measures.RESULTS: A meta-analysis of eight studies included 1070 patients was carried out to evaluate the association between GPC3 and overall survival (OS) and disease-free survival (DFS) in HCC patients. The relation between GPC3 and tumor pathological features was also assessed. Our analysis results indicated that high GPC3 expression predicted poor OS (HR: 1.96, 95% CI: 1.51-2.55) and DFS (HR: 1.99, 95% CI: 1.57-2.51) of patients with HCC. GPC3 overexpression was significantly associated with high tumor grade (OR: 3.30, 95% CI: 2.04-5.33), late TNM stage (OR: 2.26, 95% CI: 1.00-5.12), and the presence of vascular invasion (OR: 2.43, 95% CI: 1.23-4.82).CONCLUSIONS: GPC3 overexpression indicates a poor prognosis for patients with HCC, and it may also have predictive potential for HCC invasion and metastasis.

GC33 is a humanized mAb against human glypican-3 (GPC3). In the first-in-human study carried out in the USA, GC33 was well tolerated and showed preliminary antitumor activity in patients with advanced hepatocellular carcinoma. This study aimed to assess the safety, tolerability, and pharmacokinetic characteristics of GC33 in Japanese patients with advanced hepatocellular carcinoma. The study design was a conventional 3 + 3 dose-escalation design to determine the maximum tolerated dose of GC33 given i.v. at 5, 10, or 20 mg/kg weekly. Immunohistochemistry was carried out on tumor biopsies to evaluate GPC3 expression. Thirteen patients were enrolled across the three dose levels, and no patients observed any dose-limiting toxicity up to the highest planned dose of 20 mg/kg. The most common adverse events were decreased lymphocyte count, decreased natural killer cell count, increased C-reactive protein, and pyrexia. Grade 3 adverse events (increased blood pressure, decreased lymphocyte count, and decreased platelet count) were observed in two or more patients. The AUCinf showed a dose-proportional increase from the 5 mg/kg dose group to the 20 mg/kg dose group. The trough concentrations of GC33 appeared to reach a steady state after the fourth to the sixth dose. Seven of the 13 patients showed stable disease, the other six showed progressive disease. Furthermore, three patients showed long-term stable disease of more than 5 months. In conclusion, GC33 given at up to 20 mg/kg weekly was well tolerated in Japanese patients with advanced hepatocellular carcinoma.

OBJECTIVE: To explore the expression and diagnostic significance of glypican-3 (GPC3) in hepatoblastoma.METHODS: Five tissue microarray paraffin blocks were constructed to include 54 cases of hepatoblastoma. The tumor tissue samples were obtained from 3 surgical biopsies, 33 needle biopsies, 5 stage I resection tumors, and 13 stage II resection tumors after transcatheter arterial chemoembolization. Ten samples of non-neoplastic hepatic tissue adjacent to tumor were used as control. Immunohistochemical staining of GPC3 (clone 1G12) was performed. Among the 54 cases of hepatoblastoma, 22 cases were fetal subtype, 24 cases were mixed fetal and embryonal subtype and 8 cases were mixed epithelial and mesenchymal type.RESULTS: GPC3 was positive in fetal epithelial cells (54/54, 100%), but negative or weakly positive in embryonic epithelial cells in all cases of hepatoblastoma. Undifferentiated small cells and all mesenchymal components were negative for the expression. Non-neoplastic hepatocytes adjacent to tumor were negative for GPC3 expression (0/10) .CONCLUSIONS: Fetal epithelial components of hepatoblastoma express GPC3 protein detectable by immunohistochemistry. Normal hepatocytes after birth, small cell undifferentiated and embryonic epithelial components of hepatoblastoma do not or weakly express GPC3 protein. Therefore, GPC3 immunohistochemistry offers a valuable aid to the diagnosis of hepatoblastoma in infants and children.

Glycans play a critical role in physiological and pathological processes through interaction with a variety of ligands. Altered expression and dysregulation of these molecules can cause aberrant cellular function such as malignancy. Glycomics provide information of the structure and function of glycans, glycolipids, and glycoproteins such as proteoglycans, and may help to predict cancer development and progression as biomarkers. In this report, we compared the expression of proteoglycans, the content and structure of glycosaminoglycans and glycolipids between patient-matched normal and cancer tissues obtained from colon cancer patients. Tumor-related proteoglycans, glypican-3, and syndecan-1 showed downregulation in cancer tissues compared to normal tissues. In cancer tissue, the total amount of chondroitin sulfate (CS)/dermatan sulfate and heparan sulfate were lower and, interestingly, the level of disaccharide units of both 4S6S (CS-E) and 6S (CS-C) were higher compared to normal tissue. Also, overall lipids including glycolipids, a major glycomics target, were analyzed by hydrophilic interaction liquid chromatography mass spectrometry. Increase of lyso-phosphatidylcholine (phospholipid), sphingomyelin (sphigolipid), and four types of glycolipids (glucosylceramide, lactosylceramide, monosialic acid ganglioside, and globoside 4) in cancer tissue showed the possibility as potential biomarkers in colon cancer. While requiring the need for careful interpretation, this type of broad investigation gives us a better understanding of pathophysiological roles on glycosaminoglycans and glycolipids and might be a powerful tool for colon cancer diagnosis.

Glypican-3 (GPC3) has been reported to be a novel serum and histochemical marker for HCC. The positivity or negativity for GPC3 in hepatic precancerous lesions, such as dysplastic nodules (DN), has also been described. Moreover, our previous studies have demonstrated that some DN in liver cirrhosis represent monoclonal hyperplasia, and confirmed their neoplastic nature. However, additional studies must be performed to investigate further the relationship between DN with GPC3 positivity and HCC. Thus, we first investigated the expression of GPC3 in 136 HCC and 103 small DN (less than 1 cm in diameter) by immunohistochemical staining and determined the clonality of 81 DN from female patients using X-chromosome inactivation mosaicism and polymorphism of androgen receptor (AR) gene. Then we examined these samples for chromosomal loss of heterozygosity (LOH) at 11 microsatellite polymorphism sites. The results demonstrated that GPC3 immunoreactivity was detected in 103 of 136 HCC (75.7%) and 19 of 103 DN (18.4%), and the positive ratio correlated with HBsAg positivity. Clonality assays showed that 15 GPC3-positive DN from female patients, including 12 high-grade DN (HGDN), and 28 (42.4%) of 66 GPC3-negative DN, were monoclonal. In addition, among 19 GPC3-positive DN, chromosomal LOH was found at loci D6S1008 (100%, 19/19), D8S262 (52.6%, 10/19) and D11S1301 (57.9%, 11/19). However, the LOH frequency in GPC3-negative DN was 5.95% (5/84), 23.8% (20/84), and 4.76% (4/84) in three loci, respectively. Thus, we concluded that GPC3-positive DN, especially GPC3-positive HGDN, was really a late premalignant lesion of HCC.

UNLABELLED: Wnt signaling is important for cancer pathogenesis and is often up-regulated in hepatocellular carcinoma (HCC). Heparan sulfate proteoglycans (HSPGs) function as coreceptors or modulators of Wnt activation. Glypican-3 (GPC3) is an HSPG that is highly expressed in HCC, where it can attract Wnt proteins to the cell surface and promote cell proliferation. Thus, GPC3 has emerged as a candidate therapeutic target in liver cancer. While monoclonal antibodies to GPC3 are currently being evaluated in preclinical and clinical studies, none have shown an effect on Wnt signaling. Here, we first document the expression of Wnt3a, multiple Wnt receptors, and GPC3 in several HCC cell lines, and demonstrate that GPC3 enhanced the activity of Wnt3a/β-catenin signaling in these cells. Then we report the identification of HS20, a human monoclonal antibody against GPC3, which preferentially recognized the heparan sulfate chains of GPC3, both the sulfated and nonsulfated portions. HS20 disrupted the interaction of Wnt3a and GPC3 and blocked Wnt3a/β-catenin signaling. Moreover, HS20 inhibited Wnt3a-dependent cell proliferation in vitro and HCC xenograft growth in nude mice. In addition, HS20 had no detectable undesired toxicity in mice. Taken together, our results show that a monoclonal antibody primarily targeting the heparin sulfate chains of GPC3 inhibited Wnt/β-catenin signaling in HCC cells and had potent antitumor activity in vivo.CONCLUSION: An antibody directed against the heparan sulfate of a proteoglycan shows efficacy in blocking Wnt signaling and HCC growth, suggesting a novel strategy for liver cancer therapy.

Hepatoid adenocarcinoma is a rare gastrointestinal tumor and mostly reported in the stomach. Effective chemotherapy has yet to be developed to improve poor prognosis. The present study was undertaken to establish a useful cell line derived from a hepatoid adenocarcinoma, possibly leading to a new therapeutic strategy. The new human cell line VAT-39 was established from a metastatic lymph node of a 69-year-old Japanese male patient with hepatoid adenocarcinoma of the ampulla of Vater. The primary tumor and metastatic lymph node were composed of hepatoid adenocarcinoma cells exhibiting immunohistochemical reactivity for alpha-fetoprotein (AFP) and glypican-3 (GPC3). In the metastatic lymph node, Periodic acid-Schiff (PAS) staining clarified diffuse deposition of glycogen in the cytoplasm, indicating analogous characteristics to the primary hepatoid adenocarcinoma. Moreover, VAT-39 cells produced high levels of AFP in the cultured medium, and reverse-transcriptase polymerase chain reaction (RT-PCR) verified increased expression of GPC3 mRNA in this cell line. Further, we evaluated the sensitivity to major chemotherapeutic drugs against the bile duct cancer. Neither 5-fluorouracil nor gemcitabine showed particular sensitivity to this cell line. The tumorigenicity of the cultured cells was confirmed in athymic nude mice and the histological features of the explanted tumor were similar to the VAT-39 cell line. The present VAT-39 is the first hepatoid adenocarcinoma cell line that originates from the ampulla of Vater and it will be applicable for basic biological studies searching for new strategies of molecular targeted chemotherapy to this disease.